When you step onto an icy sidewalk or push off on skis, the surface can seem to vanish beneath you. For more than a century, scientists have debated why ice stays slippery, even well below freezing.

Winter Storm Fern, a rare convergence of Arctic cold and Southwest moisture, seems set to bring Arctic weather to many parts of the U.S. this weekend. With it, storm warnings included familiar ...

[CLIP: Skates cut across the ice at an ice rink, and music plays in the background.] Kendra Pierre-Louis: So we’re out here today in lower Manhattan ice-skating. There are lots of kids skating around, ...